Difficulty with CS2, Colorspace, and smugmug

mf44

Hi folks,

I am having troubles with color space and accuracy using Photoshop CS2 and smugmug. Here's my situation. I recognize that I need to convert my photos to sRGB before I upload. As such, I created an action that goes to Edit:Convert to Profile and then makes sure sRGB is selected and converts it. It then saves the image and embeds the colorspace information. When I look at the info it shows the Source colorspace as sRGB in photoshop, so I assume this is correct.

Now I upload my photos to smugmug. The problem is, however, when I view them. I'm using Safari, so I know that it's the only browser that supports colorspace. You see, when I look at the original size it shows me the photo just how I like it with vibrant colors. All the smaller versions are washed out. I was under the impression that converting to sRGB before uploading would solve this. What have I done wrong? Or is this simply not curable? I really don't want all my thumbnails to be washed out looking.

Thanks a lot for your help, I'm so lost at this point.

Mike

Plasmodium

What color space are you converting from to get to sRGB? I usually shoot in Adobe RGB, process my shot in ProPhoto RGB (the biggest RGB color space), and then convert to sRGB using the 'convert to profile' command and the 'perceptual' conversion method.

Now, I don't really trust the smaller versions of the photo on smugmug. I'm not sure what engine they're using to resample and resize the photo, but I doubt it's genuine fractals or some good resampling algorhithm. Remember that resizing a picture is a lossy and calculation-heavy process, and don't be surprised if you see adverse effects on sharpening, tone, and color.

Beyond that I'm not sure, but any difference between the different sized photos is probably a resampling problem, not a color space problem.

Harveylevine

mf44 wrote:

Hi folks,

I am having troubles with color space and accuracy using Photoshop CS2 and smugmug. Here's my situation. I recognize that I need to convert my photos to sRGB before I upload. As such, I created an action that goes to Edit:Convert to Profile and then makes sure sRGB is selected and converts it. It then saves the image and embeds the colorspace information. When I look at the info it shows the Source colorspace as sRGB in photoshop, so I assume this is correct.

Now I upload my photos to smugmug. The problem is, however, when I view them. I'm using Safari, so I know that it's the only browser that supports colorspace. You see, when I look at the original size it shows me the photo just how I like it with vibrant colors. All the smaller versions are washed out. I was under the impression that converting to sRGB before uploading would solve this. What have I done wrong? Or is this simply not curable? I really don't want all my thumbnails to be washed out looking.

Thanks a lot for your help, I'm so lost at this point.

Mike

Mike:

I had the exact same problem. The images I uploaded to Smugmug and viewed with Safari looked "wrong" (washed out or sallow). Viewing them on the Mac using Internet Explorer also looked "wrong".

I looked at my Smugmug site at work on a PC using Internet Explorer and the images looked very close to the way they appear in Photoshop on my mac.

The solution for me was to purchase a hardware monitor calibration device and build a profile for my iMac monitor (17 "). Now my Smugmug images look the same in Photoshop, Safari, and on my PC.

I knew it would help to perform a hardware calibration of my monitor, but I really didn't think it would help with the problem you described. But it did!

Hope this helps,

Harvey

DavidTO

Using aRGB caused me nothing but problems. I use sRGB from the start now, and all is good.

aRGB doesn't have more points in it, no more information, they're just spread out a bit more than sRGB, covering a wider gamut.

I know that pros say that the adobe RGB is the only way to go, but I'm not sure they're right.

Baldy has a lot to say on this...

Harveylevine

DavidTO wrote:

Using aRGB caused me nothing but problems. I use sRGB from the start now, and all is good.

aRGB doesn't have more points in it, no more information, they're just spread out a bit more than sRGB, covering a wider gamut.

I know that pros say that the adobe RGB is the only way to go, but I'm not sure they're right.

Baldy has a lot to say on this...

David:
I had bought into the "pro" view until I read the help screens at Smugmug. Now I'm not so sure. Against Baldy's very convicing argument are 16 authors all saying the opposite. So far I've stayed in Adobe RGB with my raw files right up until the time I convert to jpeg to post onto Smugmug. For my Casio images that start out as jpegs, I've stayed with sRGB space in Photoshop. I wonder if it makes enough difference to worry about. Then there's the issue of whether to convert the 8 bit jpegs into 16 bits ... There atleast the pros are divided.

Regards,

Harvey

Plasmodium

DavidTO wrote:

Using aRGB caused me nothing but problems. I use sRGB from the start now, and all is good.

aRGB doesn't have more points in it, no more information, they're just spread out a bit more than sRGB, covering a wider gamut.

I know that pros say that the adobe RGB is the only way to go, but I'm not sure they're right.

Baldy has a lot to say on this...

Have you read the Luminous Landscape thread on ProPhoto RGB? There are some other very interesting discussions of the topic:

http://www.outbackphoto.com/color_management/cm_06/essay.html,
http://www.naturephotographers.net/articles1203/mh1203-1.html.

My understanding is that Adobe RGB and sRGB differ in the breadth of the color gamut, but fundamentally they offer the same total number of colors due to their bit depth. ProPhoto RGB is different than these two in a couple respects. First, and most importantly, it is by design a 16-bit color space, so its gamut is spread over 2^16 possible colors; Adobe RGB and sRGB are based on 8-bit depth, so their gamuts are distributed over 2^8 colors. Just as important, it is a FAR larger gamut than Adobe RGB, and in fact of common color gamuts it is second in size only to Lab color.

In general is it important? Probably only if you are 1) doing a lot of image editing (thereby stretching and compressing the limits of your color gamut), 2) working with very saturated colors (which is where the larger gamuts may show their utility), 3) working with 16-bit images, and most importantly 4) printing using printers that will support the larger color gamuts AND have sufficient ink colors to represent them.

When is it definitely unnecessary? 1) If your only output is web sharing (because you're just going to have to convert to sRGB in the end anyway, as most web applications will only support sRGB), 2) shooting and working with 8-bit images, and3) printing through smugmug or other printers that only support sRGB.

Plasmodium

Harveylevine wrote:

David:
I had bought into the "pro" view until I read the help screens at Smugmug. Now I'm not so sure. Against Baldy's very convicing argument are 16 authors all saying the opposite. So far I've stayed in Adobe RGB with my raw files right up until the time I convert to jpeg to post onto Smugmug. For my Casio images that start out as jpegs, I've stayed with sRGB space in Photoshop. I wonder if it makes enough difference to worry about. Then there's the issue of whether to convert the 8 bit jpegs into 16 bits ... There atleast the pros are divided.

Regards,

Harvey

I wouldn't bother converting the 8-bit images into 16-bits. Putting 2 quarts of milk into a gallon jug doesn't give you a gallon of milk -- only 2 quarts in a larger container. The whole debate -- the bottom line of all these discussions about bit depth and color space -- is reducible to image content. Every editing step you take after leaving the RAW converter is at least minimally destructive. Cropping, saturating, sharpening, adjusting tone, levels, etc, forever alters the information content of each affected pixel. For serious image editors it is best to start out with the most information from the beginning, because it will give you the most flexibility when you hit your picture over and over and over with editing tools.

colourbox

Plasmodium wrote:

I wouldn't bother converting the 8-bit images into 16-bits.

I also wouldn't bother converting AdobeRGB to ProPhoto RGB. If you're shooting RAW, the shooting color space doesn't apply anyway, because the color space is assigned at the RAW converter. On cameras, as far as I've ever known, the color space setting only affects JPEGs and RAW previews.

I have good results using the smugmug help recommendations. Calibrate and profile the monitor at gamma 2.2 (even if it's a Mac), then shoot and edit whatever way works best, but when it comes time to upload, convert to sRGB and strip the profile. This is so different from my originals that I duplicate any JPGs bound for smugmug into a completely dedicated folder where I use iView Media Pro and Adobe Bridge to strip them of their profiles and any personal metadata I don't want to upload. My smugmug image filenames now include an SMG so that I know they are not to be used as source because they are missing profiles and some metadata. It's a couple extra steps but works best for me.

Read the smugmug help pages and blog entries as to why Safari is not quite doing color management correctly. While I'm a proud Mac user, I make the images so that they work for the majority - unprofiled monitors and browsers somewhere around gamma 2.2.

Baldy

Sounds like you're on it. The way Safari does color management is like no other. When no ICC profile is present it should assume the photo is in sRGB, but it doesn't.

Here's more from the read-it-and-weep department (but I still love the Mac):

http://blogs.smugmug.com/great-prints/2005/06/27/mac-browsers-can-you-believe-your-eyes/

Thanks,
Baldy

DavidTO

Baldy wrote:

Sounds like you're on it. The way Safari does color management is like no other. When no ICC profile is present it should assume the photo is in sRGB, but it doesn't.

Here's more from the read-it-and-weep department (but I still love the Mac):

http://blogs.smugmug.com/great-prints/2005/06/27/mac-browsers-can-you-believe-your-eyes/

Thanks,
Baldy

It's important when on a mac to at the very least use the calibration tool in sys prefs, and while there change the gamma from 1.8 to 2.2, the pc standard. That addresses PART of your blog post. But granted, grandma isn't going to do that...

Plasmodium

I wouldn't convert AdobeRGb to ProPhoto RGB either. I always save a preliminarily edited, full size file in 16-bit mode and (if it's from my camera rather than a scan) in a large color space, usually ProPhoto. Then I resize, sharpen and convert to 8-bit and sRGB for my gallery and internet purposes. The only reason in the end that I convert my RAW images to ProPhoto rather than just sRGB is that I prefer to get prints from 8-ink large gamut printers. I really hate (in particular) the oversaturated reds that are ubiquitous in sRGB, so I will almost never print from an sRGB-based printing service (sole exception being if I have to run to Wal-Mart to print something out at the very last minute for whatever reason). Thus, I like to save a big color gamut copy for potential printing purposes.

colourbox

I'm with ya there. RAW to ProPhoto to print, then to sRGB for monitors, that's what I do too.